Window sash burglar alarm



y 1959 R38. LONYGACRE" 2,885,991

wmnow SASH BURGLAR ALARM Filed Feb. 27, 1957 I NVENTOR. RussELL S. LONGACRE United States Patent WINDOW SASH BURGLAR ALARM Russell S. Longacre, York, Pa.

Application February 27, 1957, Serial No. 642,704

4 Claims. (Cl. 116-91) This invention relates to a window sash type burglar alarm and, more particularly to a burglar alarm which is self-energizing, simple in construction, andsmall in size so as to be inconspicuous when mounted in operative position upon a window sash.

Many types of burglar alarms have been developed heretofore, most of which have electrical type operating means and, in many instances, complicated control means are used which have to be set in order to ready the alarm for actuation as when a window is broken or opened, a door is forced open, or otherwise.

The principal purpose of the present invention is to provide a relatively inexpensive, easily installed burglar alarm which contains a power unit such as a spring motor, the alarm unit being small in size and readily connectable for example to the top rail of a lower sash of a conventional window installation having a plurality of relatively slidable sashes. By providing such an alarm in this location, the alarm will operate regardless of whether the lower sash is raised or the upper sash is lowered.

Another object of the invention is to provide very simple control means which either hold the alarm silent when the window sashes are closed, or permit the alarm to be sounded when relative movement between the two window sashes takes place.

Still another object of the invention is to provide latch means by which the control mechanism of the alarm is rendered inoperative in order that the sashes may be moved relatively to each other without causing the alarm to be sounded.

Details of these objects and of the invention, as well as other objects thereof are set forth in the following specification and illustrated in the accompanying drawing comprising a part thereof.

In the drawing:

Fig. 1 is a perspective view showing an exemplary installation of a window sash burglar alarm embodying the principles of the present invention, the relatively movable sashes shown therein being fragmentary.

Fig. 2 is a verticalsectional elevation taken on the line 22 of Fig. 3.

Fig. 3 is a vertical sectional elevation taken on the irregular section line 33 of Fig. 2 and illustrating the control means in position to hold the alarm silent.

Fig. 4 is a vertical sectional elevation taken on the line 44 of Fig. 1.

While the window sash type burglar alarm unit 10 is illustrated in Fig. l as being mounted upon the upper bar of a lower window sash 12, which is vertically slidable relative to the upper window sash 14, it is to be understood that the alarm unit 10 may be mounted in other suitable locations such as, for example, adjacent the lower end of the lower sash 12 so as to be movable relative to the sill of a window installation 16, or upon the upper bar of the upper sash 14 and be relatively movable to the header of the window installation 16. The principal requirement is that the alarm be mounted 'ice in such a position that when at least one of the sashes of a window installation is moved, the control mechanism of the alarm will be released in order that the alarm may be sounded.

The alarm unit 10 comprises a support 18 which conveniently may be formed from sheet metal, molded from synthetic resin, or otherwise shaped from suitable mate rial so as to be rigid. The support 18, as best seen from Figs. 2 and 3 actually comprises an enclosure having opposite walls 20 and 22 and a base 24 fixed thereto. An attaching flange 26 depends from one edge of the base 24 and preferably is provided with a plurality of screw holes 28, suitably beveled in order that bevel headed wood screws for example may be used to attach the alarm unit to the upper bar 30 of the lower sash 12 for exarnple, it being understood that the lower sash 12 is slidably movable relative to the upper sash 14.

The front wall 20 of the support 18 has a central opening 32 therein which is closed by a cover plate 34 shown in Fig. 3. Said cover plate 34 may be secured to the front wall 20 by a plurality of small screws 36, or otherwise. The cover plate 34 is centrally apertured to receive one end of winding arbor 38 for the coiled spring 40 which preferably is similar to a clock spring. The spring 40 may be contained, if desired, within a spring barrel 42 suitably secured to the support 18. Fixed to the outer end of the winding arbor 38 is a ratchet gear 44 and said gear and arbor are provided with a transverse slot 46 within which one end of a fiat winding key may be inserted for purposes of winding the spring 40. Pivotally supported by cover plate 34 is a holding pawl or click 48 which is resiliently held at one end in engagement with the teeth of the ratchet gear 44 by a curved spring 50. Thus, as the spring is wound by the aforementioned key, clockwise as shown in Fig. 2, the tapered end of click 48 will engage between a pair of the ratchet teeth to hold the spring in coiled condition.

Also mounted upon the winding arbor 38 on the interior of support 18 is a driving gear 52 which meshes with a small pinion 54, which may be a pin-type pinion if desired, and is secured upon a short shaft to which a transfer gear 56 also is fixed. Gear 56 meshes with another small pinion 58, similar to pinion 54, and to which a star wheel 60 is fixed for rotation by pinion 58. The shafts which support respectively pinion S8 and star wheel 60, and pinion 54 and transfer gear 56 extend be tween the wall 22 of support 18 and the parallel wall of spring barrel 42 which is spaced therefrom as shown in Fig. 3.

Oscillatably pivoted lever 62 is supported by a pivot 64 carried by rear wall 22 of support 18, the lever 62 also having a pair of spaced pallet points 66 which sequentially are engaged by spaced teeth of star wheel 60 in a manner similar to which a pallet lever of a watch or clock operates so as to oscillate lever 62 The end 68 of lever 62 is connected pivotally to one end of a link 70, the other end of said link being connected pivotally to the upper end of clapper 72. The clapper 72 is pivotally supported by a shaft 74 which, as best shownin Figs. 3, extends between front and rear walls 20 and 22 of support 18.

Referring to Fig. 2, it will be seen that one side of the support 18 is provided with an opening 76 through which the lower end of clapper 72 may project into engagement with the lower end of freely supported bell 78 which encloses the support 18 as shown in Figs. 2 and 3. Preferably, the ball 78 has a socket 80 which receives a fulcrum projection 82 extending upward from support 18. Thus, the bell 78 is freely supported relative to support 18 whereby, when the clapper 72 strikes the skirt of bell 78, it will be sounded audibly.

The control means for the alarm unit comprises a bell crank 84 which is connected to a suitable bracket 86 fixed to rear wall 22 of support 18 for example. One leg 88 of bell crank 84 is under constant tension by a coil spring M1 for movement toward rear wall 22 of support 18. The leg 83 of the bell crank, when disposed in the position shown in Fig. 3, will engage the clapper 72 and hold the alarm silent. However, when the outer arm of bell crank 84' is free to move counter-clockwise, as viewed in Fig. 3, the leg 88 of the bell crank will be moved toward the rear wall 22 and thereby free the clapper 72 for engagement with the bell 73.

Normally, the bell crank control means 84 is held in the position shown in Fig. 3, when the sash 12 is closed, by a keeper 92, shown in Fig. 4, which may be secured by screws or otherwise to one side of the sash frame 14. Keeper )2 has a projection or other suitable surface portion which normally engages the outer leg of hell crank 84 asshown in Fig. 4 so as to maintain the bell crank in the silent position of the alarm as shown in Fig. 3. Under such conditions, the spring 90 will be under tension but the leg 88 of the bell crank will engage the clapper 72 to hold the alarm silent. Should either the lower sash 12 be raised or the upper sash 14 be lowered however, the keeper 92 correspondingly would be moved from its restraining position shown in Fig. 4 and thus let the spring 90 move the bell crank 84 counter-clockwise and thereby free the clapper 72 for sounding the bell 78.

In order that the alarm may be rendered silent under conditions where it is desired to raise the lower sash 12 or lower the upper sash 14, a pivoted latch 94 which is supported by base 24 of support 18, for example, through the means of rivet 96, has a finger engageable handle 98 thereon by which the latch 94 may be moved to and from engagement with the lower end of bell crank 84. When engaging bell crank 84, the same will be held in the position shown in Fig. 3 to hold the alarm silent.

However, to ready the alarm for being sounded when there is relative movement between the sashes 12 and 14, the latch 94 is moved so as to be spaced from the lower end of bell crank 84.

In order that winding of the spring may take place without removing the bell 78 from the alarm unit, the front face of the bell is provided with an opening 100 through which the winding key may be inserted into the slot 46 of winding arbor 38.

From the foregoing, it will be seen that the present invention provides a small, simple, effective, and inconspicuous alarm unit 10 which may be affixed by simple means to a sash of a window assembly, preferably adjacent one side of said sash so as not to be readily visible from the exterior of the window inasmuch as the major portion of the alarm unit would be hidden by one of the side rails of the upper sash 14 for example as shown in Fig. 1. The power means for operating the alarm clapper is simple and contained within the support of the alarm unit in such manner that it readily may be wound by a simple key. Latch means are provided to maintain the alarm silent under conditions where it is desired to relatively move the sashes of the window assembly as during warm weather or at night to let air into a bedroom for example. However, it will be understood that an alarm of this nature primarily is used when the house or apartment is closed during absence of the occupants. Under such conditions, the windows are closed and the latch 94 will be moved to non-holding position of the control means 84, whereby upon movement of one sash relative to the other, the control means will be moved automatically by a spring 90 to permit the clapper 72 of the alarm to sound the bell 78 audibly.

Not only is an alarm such as described and claimed herein easily installed, but the same also is relatively in expensive to manufacture due to the reasonably small number of components and the simple assembly which is required.

While the invention has been described and illustrated in its preferred embodiment, and has included certain details, it should be understood that the invention is not to be limited to the precise details herein illustrated and described since the same may be carried out in other ways falling within the scope of the invention as claimed.

I claim:

l. A window sash burglar alarm unit for a window installation comprising in combination, a generally rectangular support attachable at the bottom to a movable window sash frame so as to extend upward therefrom, a. spring motor carried by said support, a clapper pivotally carried by said support, means interconnecting said motor and clapper and operable to oscillate the clapper, a control lever carried by the lower portion of said frame and movable between an idle position and a position in which one end of said lever engages said clapper to hold the same inactive, a bell shaped to enclose said support and supported for free resonance from the top of said support, said bell being engageable by said clapper when oscillated by said motor, the other end of said lever extending outward from said bell, and keeper means attachable to said window installation eXteriorly of said bell and in a position to engage the other end of said control lever when said window sash is closed to hold said control lever in position to engage said clapper and maintain the same inactive but release said control lever when said keeper means disengages said lever.

2. A window sash burglar alarm unit for a window sash and frame installation comprising in combination, a support attachable to a window sash frame, a spring motor carried by said support, a clapper pivotally carried by said support, means interconnecting said motor and clapper to oscillate the clapper, control means comprising a pivoted lever carried by said support and movable between an idle position and a position in which one portion of said lever directly engages said clapper to hold the same inactive, spring means engaging said pivoted lever and operable normally to move said lever out of engagement with said clapper, a bell positioned on said unit to be engageable by said clapper when oscillated by said motor, and keeper means attachable to a portion of said window installation between which and said window sash frame there is relative movement, said keeper means being positioned upon said portion so as directly to engage said control lever of said alarm unit when said window sash is closed to hold said control lever in position to engage said clapper to maintain the same inactive but release said control lever when said keeper means disengages said control lever.

3. A window sash burglar alarm unit for a window sash and frame installation comprising in combination, a support attachable to a window sash frame, a spring motor carried by said support, a clapper pivotally carried by said support, means interconnecting said motor and clapper to oscillate the clapper, control means comprising a pivoted lever carried by said support and movable between an idle position and a position in which one portion of said lever directly engages said clapper to hold the same inactive, a bell positioned on said unit to be engageable by said clap-per when oscillated by said motor, said bell being shaped to enclose said support and the motor and clapper carried thereby, and keeper means attachable to a portion of said window installation between which and said window sash frame there is relative movement, said keeper means being positioned upon said portion so as directly to engage said control lever of said alarm unit when said window sash is closed to hold said control lever in position to engage said clapper to maintain the same inactive but release said control lever when said keeper means disengages said control lever.

4. A window sash burglar alarm unit for a window sash and frame installation comprising in combination, a supportattachable to a window sash frame, a spring motor carried by. said support, a clapper pivotally carried by said support, means interconnecting said motor and clapper to oscillate the clapper, control means comprising a pivoted lever carried by said support and movable between an idle position and a position in which one portion of said lever directly engages said clapper to hold the same inactive, a bell positioned on said unit to be engageable by said clapper when oscillated by said motor, a latch movably supported by said alarm unit adjacent said pivoted lever and movable to engage said lever when the same is in position to engage said clapper to hold said lever in said position until said latch is removed from engagement with said lever, and keeper means attachable to a portion of said window installation between which and said window sash frame there is relative movement, said keeper means being positioned upon said portion so as directly to engage said control lever of said alarm unit when said window sash is closed to hold said control lever in position to engage said clapper to maintain the same inactive but release said control lever when said keeper means disengages said control lever.

Winsett May 15, 1934 Counts Sept. 23, 1952 

